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1/* SPDX-License-Identifier: GPL-2.0-only */2/*3 * Copyright 2023 Red Hat4 */5 6#ifndef VDO_PHYSICAL_ZONE_H7#define VDO_PHYSICAL_ZONE_H8 9#include <linux/atomic.h>10 11#include "types.h"12 13/*14 * The type of a PBN lock.15 */16enum pbn_lock_type {17 VIO_READ_LOCK,18 VIO_WRITE_LOCK,19 VIO_BLOCK_MAP_WRITE_LOCK,20};21 22struct pbn_lock_implementation;23 24/*25 * A PBN lock.26 */27struct pbn_lock {28 /* The implementation of the lock */29 const struct pbn_lock_implementation *implementation;30 31 /* The number of VIOs holding or sharing this lock */32 data_vio_count_t holder_count;33 /*34 * The number of compressed block writers holding a share of this lock while they are35 * acquiring a reference to the PBN.36 */37 u8 fragment_locks;38 39 /* Whether the locked PBN has been provisionally referenced on behalf of the lock holder. */40 bool has_provisional_reference;41 42 /*43 * For read locks, the number of references that were known to be available on the locked44 * block at the time the lock was acquired.45 */46 u8 increment_limit;47 48 /*49 * For read locks, the number of data_vios that have tried to claim one of the available50 * increments during the lifetime of the lock. Each claim will first increment this51 * counter, so it can exceed the increment limit.52 */53 atomic_t increments_claimed;54};55 56struct physical_zone {57 /* Which physical zone this is */58 zone_count_t zone_number;59 /* The thread ID for this zone */60 thread_id_t thread_id;61 /* In progress operations keyed by PBN */62 struct int_map *pbn_operations;63 /* Pool of unused pbn_lock instances */64 struct pbn_lock_pool *lock_pool;65 /* The block allocator for this zone */66 struct block_allocator *allocator;67 /* The next zone from which to attempt an allocation */68 struct physical_zone *next;69};70 71struct physical_zones {72 /* The number of zones */73 zone_count_t zone_count;74 /* The physical zones themselves */75 struct physical_zone zones[];76};77 78bool __must_check vdo_is_pbn_read_lock(const struct pbn_lock *lock);79void vdo_downgrade_pbn_write_lock(struct pbn_lock *lock, bool compressed_write);80bool __must_check vdo_claim_pbn_lock_increment(struct pbn_lock *lock);81 82/**83 * vdo_pbn_lock_has_provisional_reference() - Check whether a PBN lock has a provisional reference.84 * @lock: The PBN lock.85 */86static inline bool vdo_pbn_lock_has_provisional_reference(struct pbn_lock *lock)87{88 return ((lock != NULL) && lock->has_provisional_reference);89}90 91void vdo_assign_pbn_lock_provisional_reference(struct pbn_lock *lock);92void vdo_unassign_pbn_lock_provisional_reference(struct pbn_lock *lock);93 94int __must_check vdo_make_physical_zones(struct vdo *vdo,95 struct physical_zones **zones_ptr);96 97void vdo_free_physical_zones(struct physical_zones *zones);98 99struct pbn_lock * __must_check vdo_get_physical_zone_pbn_lock(struct physical_zone *zone,100 physical_block_number_t pbn);101 102int __must_check vdo_attempt_physical_zone_pbn_lock(struct physical_zone *zone,103 physical_block_number_t pbn,104 enum pbn_lock_type type,105 struct pbn_lock **lock_ptr);106 107bool __must_check vdo_allocate_block_in_zone(struct data_vio *data_vio);108 109void vdo_release_physical_zone_pbn_lock(struct physical_zone *zone,110 physical_block_number_t locked_pbn,111 struct pbn_lock *lock);112 113void vdo_dump_physical_zone(const struct physical_zone *zone);114 115#endif /* VDO_PHYSICAL_ZONE_H */116